A unity of the self or a multiplicity of locations? How the graphesthesia task sheds light on the role of spatial perspectives in bodily self-consciousness

Integrating multisensory stimuli from a self-centred perspective is crucial for the unity of the self. On the other hand, understanding external space and communicating spatial knowledge with others necessitate the adoption of decentred perspectives. How do we juggle these two requirements? In this article, we review those studies that have used the graphesthesia task in order to investigate the perspectives that people adopt when interpreting ambiguous tactile symbols (e.g., b, d, p, and q). With such ambiguous symbols, self-centred and decentred perspectives conflict with one another. The results reviewed here reveal that the perspectives adopted vary significantly with spatial, personal, and interpersonal factors. Such findings suggest that the self can adopt a multiplicity of spatial locations. However, the unity of the self can partly be explained by the predominance of a head-centred perspective. On the other hand, perspective taking abilities contribute to the distinction between self and others, reinforcing self-consciousness.